Die casting apparatus



Ap 8, 1953 w. c. FROMMER DIE CASTING APPARATUS- 4 Sheets-Sheet 1 FiledDec. 15, 1955 INVENTOR. v #44 1/4 4. Fran/v5? BY April 1958 w. c.FROMMER 2,829,409

DIE CASTING APPARATUS Filed Dec. 15, 1955 4 Sheets-Sheet 2 otmwfv April8, 1958 I w. c. FROMMER 2,829,409

DIE CASTING APPARATUS Filed Dec. 13, 1955 4 sh ets-sheet s INVENTOR.fizz/4w dfF M/VER April 1953 w. c. FROMMER 2,829,409

DIE CASTING APPARATUS Filed Dec. 15, 1955 4 Sheets-Sheet 4 W 35 "LEE P Iv k INVEN TOR. a #24149 {7900/4677 DIE CASTING APPARATUS William C.Frommer, Elizabeth, N. J., assignor to Star Expansion IndustriesCorporation, New York, N. Y., a corporation of Delaware ApplicationDecember 13, 1955, Serial No. 552,799

1 Claim. v(Cl. 22-93) Ihis invention relates to die casting apparatusand particularly to apparatus for casting a plurality of groups ofmultiple units of articles having internal threads therein.

The die casting unit comprises a movable die and a closure or stationarydie, the die member in which the threaded articles are to be cast havingthreaded cores therein, and means for rotating the cores when the dieshave been separated whereby the castings will be ejected from the moldcavities in the die.

The invention has for its salient object to provide apparatus of thecharacter described in which the mold cavities are disposed in themovable-die and the threaded cores can be rotated to eject the castingswhen the movable die is opened or moved away from the stationary die orclosure.

Another object of the invention is to provide apparatus of the characterdescribed so constructed that a plurality of groups of units can be castsimultaneously.

Another object of the invention is to provide apparatus of the characterdescribed so constructed that a plurality of groups of units can be castsimultaneously and can thereafter be ejected simultaneously.

Further objects of the invention will appear from the followingspecification taken in connection with the drawings which form a part ofthis application, and which Fig. 1 is a plan view of apparatusconstructed in accordance with the invention;

Fig. 2 is a plan view of the apparatus showing the movable die in openposition and illustrating diagrammatically the means whereby the drivingconnections between the core driving mechanism and the threaded coreswill be set in operation when the movable die is opened;

Fig. 3 is a view, partly in plan and partly in section, showing themovable die and the driving connections for the threaded cores therein;

Fig. 4 is a face view of the movable die, parts being omitted for thesake of clearness, and illustrating the driving connections for thethreaded cores;

Fig. 5 is a plan view of the multiple unit casting made in theapparatus;

Fig. 6 is an elevational view of one of the units cast; and

Fig. 7 is a sectional elevation of the casting shown in Fig. 6.

The invention, briefly described, consists of die casting apparatuscomprising a die casting unit and mechanism connected thereto forrotating the threaded cores in the die to eject the castings from themold cavities. The die casting unit comprises a movable die which ismovable toward and away from a stationary die, the mold cavities beingformed in the movable die and the molten metal being introduced througha gate in the stationary die into the mold cavities under pressure whenthe movable die is closed upon the stationary die or closure. The gateis disposed centrally in the movable die and the mold cavi- 2 ties andpassages thereto for forming the groups ofunit are disposed laterally ofthe gate.

The apparatus further comprises core driving mechanism which is sooperated and so connected to the threaded cores in the movable die thatwhen the movable die is opened the connections to the core drivingmechanism are closed, thereby operating the driving connections androtating the cores in a direction to eject the groups of cast units fromthe movable die.

Further details of the invention will appear from the followingdescription.

In the particular embodiment of the invention illustrated in thedrawings, the die casting apparatus is shown at A and the core drivingmechanism is shown at B,

these parts of the apparatus being disposed side by side.

The die casting apparatus A is mounted on .a base 10' and comprises amovable die 11 carried by a block 12 slidably mounted on rods 13 and 14.The die casting apparatus further comprises a stationary die 15 which iscarried by astationary block 16 mounted on the rods 13 and 14.

The block 12 and the movable die 11 are moved toward and away from thestationary die by means of a rod 20 which is connected by suitabletoggle mechanism, not

shown, to a plunger rod 21 which extends into a pneumatic cylinder 22.This cylinder has a piston therein which-is operated pneumatically inthe usual manner and moves alternately in opposite directions by asuitable control mechanism to close and open the movable die. It will beunderstood that the rod 20 and piston rod 21 are slidable throughsuitable bearings.

The construction of the movable die is shown particularly in Figs. 3 and4. As shown in Fig. 3, the stationary die 15 has a central opening orgate 25 theretbrough, and the molten metal under pressure is introducedinto the gate 25 through a suitable conduit or nipple 28. As shown inFig. 4, the gate 25 communicates with conduits 26 and 27 extendinglaterally from the gate and each of these conduits has a series ofbranch conduits 30, 31, 32, 33 and 34 which extend laterally from theconduits 26 and 27 and communicate with mold cavities 35. In each of themold cavities there is disposed a threaded core pin 36 which is carriedby a spindle 37. On each of the spindles 37 on one side of the gatethere are mounted gears 38 which mesh with a gear 39 mounted on aspindle 40, which also has mounted thereon a gear 41 which meshes with agear 42 carried by a spindle 43. The spindle 43 has a sprocket 44 whichis driven by a chain 45, which is also mounted on a sprocket 46 splinedto a shaft 47 of the core driving mechanism B.

The gear 42 also meshes with a gear 50 mounted on a spindle 51, whichhas also mounted thereon a gear 52 which corresponds to the gear 39 onthe spindle 40. Gear 52 meshes with gears 53 on spindles 54 which carrythe threaded core pins in the unit at the other side of the gate 25.

After the movable die has been closed by being moved to position againstthe stationary die, the molten metal is introduced through the conduitor nipple 28 into the gate 25 and is forced laterally through theconduits or grooves 26 and 27 and into the branch conduits from whichthe metal passes into the mold cavities. After this operation has beencompleted, the movable die is moved away from the stationary die and, ina manner hereinafter described, the driving connections for the corerotating mechanism are closed and the cores are rotated in a directionto eject the castings from the mold cavities.

The core driving mechanism will now be described. The shaft 47 ismounted in suitable bearings 60, 61 and 62 on a base 63. The sprocket 46on the shaft 47 is mounted on or carried by a grooved collar 65. Aforked thereon a pulley 72 driven from any suitable source of.

power. Shaft 47 also has mounted thereon a brake 73.

The driving connections for operating the clutch and the brake are showndiagrammatically in Fig. 2. A switch 80, has a switch operating "pin 81-disposed in the path of movement of an abutment 82 carried by the block12. As the movable die 11 moves: to open position, as shown in Fig. 2,the abutment 82 will cause the pin 81 to close the switch 80, therebyconnecting the power line shownat 83 and 84 toleads 85 and 86 which arecon nected to a solenoid valve 87. This valve is connected to an airpressure conduit 88 and when the switch 80 is closed the solenoid isoperated to cause the valve to open, permitting, the air from the airpre sure line 88 to enter a conduit 89 from which air is conductedthrough a branch conduit 90 to the clutch 70. Moreover, the conduit 89is connected to the brake 73.

Thus, when the movable die opens, the switch S9 is closed,.energizingthe solenoid valve 87 and causing this valve to connect the air pressureline 88 to the conduit 89 and branch conduit 90, closing the clutch 70which is normally open, and releasing the brake 73 which is normallyclosed. Since the chain45 which drives the connections for the threadedcore pins is mounted on a sprocket 46 which is splined to the shaft 47,and since this sprocket is carried by the collar 65 which in turn moveswith the movable die, the chain 45 can drive the core pins to eject thecastings when the movable die is opened.

Although one specific embodiment of the invention has been particularlyshown and described, it will be understood that the invention is capableof modification and unit comprising a movable die having mold cavitiesthere.

in, rotatable threaded core pins in the mold cavities, and a stationarydie closure, said operating unit having a splined drive shaft and beingpositioned alongside said die casting unit, a sprocket splined to saidshaft, means on said movable die for connection by a chain to saidsprocket for rotating said core pins, and bracket'means connected to themovable die for moving said sprocket along the splined shaft on theoperating unit as the movable die moves away from the die closure tomaintain the driving connection between said units in any position ofsaid movable die.

References Cited in the file of this patent UNITED STATES PATENTSMcIntosh Nov. 22, 1938 2,137,539 2,154,745 Hedgpcth Apr. 18, 19392,217,661 Anderson Oct. 15, 1.940 2,327,665 Peat Aug. 24, 1943 2,384,809Bullard et al Sept. 18, 1945 2,391,527 Tracy Dec. 25,-1945 2,441,525Zesbaugh May 11, 1948 2,454,561 Lester Nov. 23, 1948 2,483,094 HarveySept. 27, 1949 2,513,216 Sullivan et a1. June 27, 1950 2,579,952 MorinDec. 25, 1951 2,583,093 Emmert et al. Jan. 22, 1952 FOREIGN PATENTS510,668 Great Britain Aug. 4, 1939 979,960 France a- Dec. 20, 1950

